AB0208 LONG-RUN RELATIONSHIP ASSESSMENT OF AIR POLLUTANTS ON RHEUMATOID ARTHRITIS DISEASE ACTIVITY SCORE: EVIDENCE FROM THE VECM APPROACH
Authors: A. Alsaber, A. Al-Herz, J. Pan, A. Al-Sultan
Journal: Annals of the Rheumatic Diseases (2022)

Background Current findings on the impact of air quality conditions on rheumatoid arthritis (RA) are sparse and not conclusive. Objectives To investigate the relationship between air pollutants and RA disease activity scores on a short and a long time period using a multivariate time series model. Methods Data on RA patients were extracted from the Kuwait Registry for Rheumatic Diseases (KRRD) from four major hospitals in Kuwait from January 2013 to December 2017. Data on air ambient pollutants (ozone O3, sulfur dioxide SO2, nitrogen dioxide NO2) were extracted from four Kuwait Environmental Public Authority (K-EPA) Air Monitoring Stations through Environmental Monitoring Information System of Kuwait (eMISK), corresponding to the patients residential areas from January 2013 till December 2020. A multivariate time series approach using Evidence from vector error correction model (VECM) was employed to investigate the effect of air ambient pollutants emissions on DAS28 over that period. Results A total of 1,809 RA patients and 10,215 hospital visits were included, 63% females, mean age 54 years, mean disease duration 9.2 years and 77% had rheumatoid factor positive. A significant correlation was found between DAS-28 and SO2, NO2 and O3 (p=0.012, 0.029, 0.039 respectively). According to the Granger causality test and VECM, emissions of NO2, and O3 had a positive short-term effect on DAS28 among RA patients. Impulse response test results showed that for some locations in Kuwait there is a short-term positive causal relationship between emissions of NO2 and DAS28, due to sources of pollution surrounding the locations. The results showed that the short run effect for NO2 with lags 1 to 4 days had a positive relationship with DAS-28 which means, there is 1% increase in DAS-28 for every 0.0182 increase in NO2 emission. Our results revealed that 36% of discrepancy between the overall relationship between DAS-28 and air pollution is corrected each year. Conclusion Increased concentrations of air pollutants may increase the risk of RA activity. VECM time series model can be used as a tool to predict changes in disease activity based on air pollutants up to 8 days. We recommend that a regular broadcast is issued by health authorities to RA patients to help predict changes in disease activity. Warning about air pollution may be tailored according to the patient’s residential area. Government should take serious decisions to help minimize air pollution in the residential areas. References [1]Chang, K.-H., Hsu, C.-C., Muo, C.-H., Hsu, C. Y., Liu, H.-C., Kao, C.-H., Chen, C.- Y., Chang, M.-Y., and Hsu, Y.-C. (2016). Air pollution exposure increases the risk of rheumatoid arthritis: a longitudinal and nationwide study. Environment International, 94:495–499. [2]Alsaber, A., Pan, J., Al-Herz, A., Alkandary, D. S., Al-Hurban, A., Setiya, P., Group, K., et al. (2020). Influence of ambient air pollution on rheumatoid arthritis disease activity score index. International Journal of Environmental Research and Public Health, 17(2):416. [3]Adami, G., Viapiana, O., Rossini, M., Orsolini, G., Bertoldo, E., Giollo, A., ... &amp; Fassio, A. (2021). Association between environmental air pollution and rheumatoid arthritis flares. Rheumatology. [4]Al-Herz, A., Al-Awadhi, A., Saleh, K., Al-Kandari, W., Hasan, E., Ghanem, A., Abutiban, F., Alenizi, A., Hussain, M., Ali, Y., et al. (2016). A comparison of rheumatoid arthritis patients in kuwait with other populations: results from the krrd registry. Journal of Advances in Medicine and Medical Research, pages 1–11. [5]Al-Hurban, A., Khader, S., Alsaber, A., and Pan, J. (2021). Air quality assessment in the state of kuwait during 2012 to 2017. Atmosphere, 12(6):678. Figure 1. Long-term (2012-2020) trends of NO2 concentrations and DAS-28 calculated using the smooth trend method based on the mean measurements for four locations in Kuwait Disclosure of Interests None declared